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Model 90 Stuck At One Volume Level
#9

So I've gone over the complete schematic (for the 3rd time now) and highlighted every circuit. I find nothing that's out of place, open, shorted etc. I still have about 50% volume with no control over it. I checked the AVC at the junction of #46 & #48 reading to chassis ground and I do see a substantial change in the negative voltage at this point when I go on and off of station.

I ground the grid of the Det. Amp. and I still have the same volume. I remove the Det. Amp. tube and my volume goes away completely. This is about all I can tell you. I'M STUMPED!

EDIT: There is one thing that I have in question. The #55 choke. It is obviously an aftermarket product. I read about 150 ohms across it's leads. I have no reference on this so I don't even know if it matters.

Pepper

"It's Nice To Be Nice To The Nice"
Major Frank Burns Mash 4077th


Messages In This Thread
Model 90 Stuck At One Volume Level - by Pepperoni - 04-12-2012, 03:54 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-12-2012, 09:19 PM
RE: Model 90 Stuck At One Volume Level - by Pepperoni - 04-13-2012, 03:39 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-14-2012, 02:44 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-14-2012, 02:52 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-14-2012, 06:16 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-14-2012, 08:51 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-15-2012, 12:04 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-15-2012, 01:26 PM



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